Vehicle impact sensing system

ABSTRACT

A vehicle impact sensing system for detecting impact events to a vehicle, and allowing deployment decisions of passive restraint devices based on information gathered and relayed regarding such impact events. The sensing system includes one or more sensor elements capable of directly detecting vehicle deformation occurring as a consequence of the impact event. The sensor elements generate an output that varies upon deformation of the element. The sensor elements are in communication with a restraints control module. Upon deformation of the sensor element, the control module receives impact signals from the sensor elements based upon the altered output, and discriminates between impact events that warrant deployment of a passive restraint, such as a side air bag, and those that do not. The control module utilizes information gathered from the sensor elements to make deployment decisions, such as which restraint to deploy and the appropriate degree of deployment.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application No.60/156,165, filed Sep. 27, 1999.

FIELD OF THE INVENTION

The present invention relates to a sensing system employed to detectvehicular impact events; and more particularly to a vehicular impactsensing system that utilizes sensors to directly detect vehicledeformation by impact events and actuate restraints, such as inflatablerestraints, in the motor vehicle.

BACKGROUND OF THE INVENTION

Almost all passenger motor vehicles presently produced include some typeof impact deployed restraint system to protect vehicle occupants, orothers, during a vehicle impact event. Such restraint systems mayinclude, for example, front and side airbags within the passengercompartment, side curtains, inflatable seat belts, and seat beltpretensioners. A restraint system may also include deployable restraintsfor the protection of pedestrians involved in impacts with the vehicle,such as pedestrian airbags and hood release mechanisms. Sensing systemstypically control the deployment of such restraints by detecting theoccurrence of a vehicle impact event.

During most impact events, the opportunity to provide occupant restraintexists only for a very brief period of time. Furthermore, inadvertentdeployment of a restraint, such as an airbag, is undesirable. Therefore,to be most effective, impact deployed restraints must deploy quicklywhen needed, and only when actually needed. To this end, impact sensorsmust be able to discriminate between severe and relatively harmlessimpact events and also be insensitive to mechanical inputs which are notassociated with crash events. Most importantly, however, the design ofthe sensor must allow for rapid detection of the impact event andtransmission of relevant information to allow for effective deploymentdecisions. The need for a sensor which allows for rapid deploymentdecisions is particularly great with side airbags, where the crush zoneis much smaller than that associated with front airbags, and the timeavailable for a deployment decision is likewise shorter.

Several types of sensors have been used for detection of impact eventsin vehicles. For example, sensors comprised of piezoelectric cables,accelerometers, pressure sensors and crush-zone switches, have beenutilized. While these sensors can operate adequately, it is desirable toimprove the ability of vehicle impact sensing systems to discriminatebetween impact events, such as vehicle crashes, that warrant deploymentof a passive restraint, and those that do not, such as a minor impactwith a shopping cart. Furthermore, it is desirable to improve theability of the sensor to provide information regarding the impact, suchas its location and relative size, thereby increasing the effectivenessof subsequent deployment decisions.

Consequently, there is a need for an impact sensing system that utilizessensors capable of relaying information about an impact and makingdeployment decisions based on such information.

SUMMARY OF THE INVENTION

In its embodiments, the present invention comprises a vehicle sensingsystem that utilizes sensor elements to directly detect deformation ofthe vehicle and provide information regarding the impact. Directdetection of vehicle deformation, as opposed to indirect detection,allows the sensor to relay more accurate and detailed informationregarding the impact event. As a consequence, the sensing systemaccording to the present invention has an ability to discriminate amongimpact events, and allows for effective deployment decisions.

The sensing system of the present invention includes a sensor elementfor such direct detection of vehicle deformation. The sensor is mountedin a manner that allows the sensor to directly detect an impact event.That is, the sensor operates as a consequence of its direct physicalinvolvement in the impact. The sensor is in electronic communicationwith a controller, which receives and interprets electronic signals fromthe sensor.

The sensing system of the present invention can be utilized to directlyobtain information about impact events in a variety of vehiclelocations. For example, sensors can be located in the vehicle door togather information concerning side impacts. Likewise, a sensor can beembedded directly into a vehicle bumper to obtain information regardingfrontal impacts. Wherever located, the sensor elements provideinformation regarding an impact, allowing for more effective deploymentdecisions. The sensor element preferably constitutes a bend sensitiveresistance element having conductive layers such as an ink which hasbeen printed onto a substrate and treated to produce cracks in itsstructure. When the bend sensitive resistance element is bent, such asoccurs in a vehicle crash, the cracks open and increase the resistanceof the element. The bend sensitive resistance element may be a singleunitary element, or a plurality of independent elongate elementshorizontally situated so as to be capable of providing azimuthalresolution of the impact event. The bend sensitive resistance elementmay either be disposed on a structural element of the vehicle, such aswithin a vehicle door, or contained within a sealed housing. Use of asealed housing protects it from environmental contamination while alsoimparting a modular design that facilitates installation. Furthermore,the housing may define functional elements that increase thecapabilities of the sensing system. For example, the housing may definecrush actuators that facilitate the transmission of the impact to theresistance element. Means are adapted for mounting the housing adjacenta structural member of the vehicle, and extending generally along themember.

The controller subsequently makes deployment decisions based on thesignals received from the sensor element. The present invention furthercontemplates a method of discriminating among impact events, the methodcomprising the steps of: directly sensing vehicle deformation via thesensor; producing a corresponding electronic deformation signal;determining the severity of the impact as compared to a threshold value;and actuating at least one deployable restraint if the threshold isexceeded by the severity of the impact.

Accordingly, an object of the present invention is to provide a sensingsystem that employs a sensor element to directly detect vehicledeformation and subsequently to provide an electronic signal containinginformation regarding the deformation.

Another object of the present invention is to provide a restraintscontrol module which utilizes the information within the electronicsignal to make deployment decisions for the restraints of the vehicle.

An advantage of the present invention is that the sensing system caninclude sensor elements arranged in a manner that provides a degree ofazimuthal resolution regarding deformation caused by an impact event,allowing the sensors to provide more specific information regarding theimpact.

Another advantage of the present invention is that the sensor elementprovides a variable output that is used to discriminate between variousimpact situations, thus improving passive restraint deploymentdecisions.

Further objects and advantages of the present invention will becomeapparent by reference to the following description of the preferredembodiment and appended drawings wherein like reference numbers reflectthe same feature, element or component.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view of a vehicle, including sensor elements,in accordance with the present invention;

FIG. 2 is a schematic side view of a vehicle door, with a sensor elementmounted thereon in accordance with the present invention;

FIG. 3 is a schematic plan view of a vehicle bumper with a sensorassembly associated therewith in accordance with the present invention;

FIG. 4 is a schematic view of a unitary bend sensitive resistanceelement in accordance with the present invention;

FIG. 5 is a schematic view of a plurality of deformation sensor elementscapable of providing azimuthal resolution in accordance with the presentinvention;

FIGS. 6 a–6 c are graphical illustrations of the approach of the side ofa vehicle containing a deformation sensor element to a pole and impacttherewith, in accordance with the present invention; and

FIGS. 7 a–7 c are graphical illustrations of the sensor output,corresponding to the impact depicted in FIGS. 6 a–6 c, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A vehicle 10 having several deployable restraints and including thepresent invention is illustrated in FIGS. 1 and 2. The vehicle has front12 and rear 14 seats in a passenger compartment 16. Mounted in proximityto each seat is a seat belt 18, each of which may be equipped withpretensioners 20 as deployment restraints. Mounted in front of the twofront seats 12 are front airbags 22. The illustrated vehicle 10 includestwo front doors 24 and two rear doors 25, all of which may include aside airbag 26 mounted alongside, adjacent the front 12 and rear 14seats. The vehicle 10 has a front bumper 28 with a pedestrian airbag 30mounted in proximity to the bumper 28.

The vehicle 10 may be equipped with accelerometers, a first frontalaccelerometer 32 oriented to sense longitudinal acceleration of thevehicle and a second side accelerometer 34 oriented to senseside-to-side (i.e., lateral) acceleration. Alternatively, the twoaccelerometers 32, 34 can be replaced with a single dual-axisacceleration sensor if so desired. These accelerometers 32, 34 areelectronically connected to and in communication with a restraintscontrol module 36.

The impact sensing system 35 of the present invention comprisesdeformation sensor elements 38 located at various positions throughoutthe vehicle, a restraints control module 36, and electrical connections40 between the sensor elements 38 and the restraints control module 36.The sensor elements 38 of the current invention may be utilized inseveral areas of the vehicle. Generally, the sensor elements 38 will bemounted in areas around the body of the vehicle 10 in which impactsensing is desired, i.e., areas in which impact events are known tooccur. For example, the sensor elements 38 may be disposed within a door24 of the vehicle 10 for detecting side impact events. Also, a sensorelement 38 may be disposed near or within a bumper 28 of the vehicle 10.So disposed, the element 38 can be utilized to monitor for impact eventsinvolving pedestrians. Other locations may, of course, be desirable. Nomatter where located, the sensor element 38 is disposed in a manner thatallows direct detection of an impact event. That is, the sensor element38 is disposed in a manner that ensures its physical involvement in animpact event generating sufficient deformation of the vehicle 10. Theterm deformation sensor is used to describe sensors capable of thisdirect physical involvement in vehicle impact events causing sufficientdeformation of the vehicle 10. For example, as shown in FIG. 2, thesensor element 38 may be disposed on a structural element of a vehicledoor 24. In this configuration, the sensor element 38 will directlyparticipate in a side impact event affecting the vehicle door 24. Also,for monitoring pedestrian and frontal impact events, the sensor element38 may be directly embedded in the compressible material of the bumper28. The position of the sensor element 38 allows the sensing system 35to discriminate among impact events. For example, the outer skin 42 of avehicle door 24 and the outer layer of a vehicle bumper 28 arefrequently exposed to impact events not warranting deployment of apassive restraint. A slight indentation to either of these structuralelements does not warrant deployment. Therefore, positioning the sensorelement 38 on the surface of either of these structural elements maylead to unnecessary deployment. Positioning the sensor element 38sufficiently underneath the outer skin 42 of the structural elementwhile ensuring its participation in significant impact events eliminatessuch unnecessary deployments.

FIG. 2 illustrates an example of the sensor element 38 mounted in avehicle door 24. The sensor element is positioned underneath the outerskin 42 and near a main structural element, such as a structuralreinforcement beam 44. The sensor element 38 can be mounted thereto viaattachment points 46. Alternatively, the sensor element 38 can bedisposed within a housing member (not illustrated), and the housingmember can be mounted securely to the reinforcement beam 44 viaattachment points 46. The attachment points 46 can be fasteners,welding, etc., so long as the sensor element 38 and/or housing issecurely and rigidly mounted to the reinforcement beam 44.

FIG. 3 illustrates an example of the sensor element 38 mounted near thefront bumper 28. The sensor element 38 is located behind the outer layerof the bumper 28, and may either be directly embedded in thecompressible material of the bumper 28, or be mounted behind the bumper28 in a manner similar to that described above for the sensor element 38located within a vehicle door 24. This sensor element 38 will detectimpacts to the front bumper 28, and demonstrates the ability of thesensing system 35 to discriminate among impact events based on theseverity of the event. Depending on the severity and the force of theimpact detected by the sensor element 38, the restraints control module36 may deploy either a pedestrian airbag 30, for minor impacts typicalof those with pedestrians, or the front 22 and/or side 26 airbags formajor impacts such as vehicle crashes. The ability to discriminatebetween these two very different types of impacts is developed morefully below.

Each sensor element 38 is in electrical communication with therestraints control module 36 via electrical connections 40. There may bea signal-processing module 48 electrically situated between the sensorelements 38 and the restraints control module 36, i.e., the signalprocessing module 48 is electrically connected to both the sensorelements 38 and the restraints control module 36. The restraints controlmodule 36 is electrically connected to and in communication with thedeployable restraints of the vehicle 10.

In the preferred embodiment, the sensor element 38 constitutes a bendsensitive resistance element 50. Bend sensitive resistance elements,such as the flexible potentiometer disclosed in U.S. Pat. No. 5,583,476to Langford, provide electrical signals that vary as the element isdeformed. A bend sensitive resistance element 50 is only one example ofthe type of sensor that can be used as the sensor element 38 in thesensing system 35 of the present invention. As such, the specificexample of a bend sensitive resistance element 50 is only illustrativein nature and is not intended to limit the scope of the presentinvention in any way.

Preferably, the bend sensitive resistance element 50 is comprised of arectangular ink strip 52 composed of a conductive ink which has beentreated to produce cracks in the ink, a flexible substrate 54, andelectrical connectors 56 for connecting the conductive ink strip 52 andthe restraints control module 36. The flexible substrate 54 ispreferably about 1″ wide and has a length approximately equal to thestructural element being monitored. In one embodiment, the ink strip 52constitutes a single continuous strip of the conductive ink having alength slightly less than that of the flexible substrate. Preferable inthis embodiment, the ink strip 52 is approximately ¼″ in height, and hasa length approximately equal to the length of the structural element tobe monitored. For example, for a bend sensitive resistance element 50utilized to monitor for side impacts, the ink strip 52 preferably has alength approximately equal to the length of the appropriate vehicle door24 and is disposed on a flexible substrate 54 slightly longer in length.

It will be appreciated that the flexible substrate 54 can varysignificantly from the dimensions detailed above. For example, thesubstrate 54 can take a size and form approximately equal to theinterior space of a door 24 panel. In this configuration, ink strips 52could be disposed in a variety of patterns along the flexible substrate54, providing a multitude of deformation sensors. The patterns could bedesigned to mimic high-probability impact sites. It will be furtherappreciated that the ink strips 52 can vary from the dimensions detailedabove to meet specific impact monitoring needs.

In an alternate embodiment illustrated in FIG. 5, the conductive ink isarranged into several smaller strips 52 each in independent electricalcommunication with the restraints control module 36. In this embodiment,the smaller ink strips 52 are disposed horizontally relative to eachother, i.e., end-to-end, along a unitary flexible substrate 54. Thesmaller ink strips are preferably about ¼″ in height by approximately 4″in length. As in the previous embodiment, the flexible substrate 54 ispreferably about 1″ in height and has a length approximately equal tothe structural element being monitored. An appropriate number of smallerink strips 52 necessary to span the length of the flexible substrate 54is disposed on the flexible substrate 54. It has been determined that,for a typical front vehicle door 24, seven ink strips 52 of thepreferable dimensions, laid end-to-end on the flexible substrate 54provide adequate coverage of the span.

Arranged in this manner, the smaller ink strips 52 act as individualbend sensitive resistance elements 50, providing a degree of azimuthalresolution. For example, when an impact event occurs near the latch ofthe door 24, causing deformation only in that area, the element 50located in that area will deform, and therefore it will be the onlyelement 50 that relays a deformation signal to the restraints controlmodule 36. This localization of the impact will allow the restraintscontrol module 36 to better discriminate among severe and non-severeimpact events. In contrast, if the element 50 constitutes a single,continuous ink strip 52 along the span, no such localization of theimpact occurs. For example, when an impact occurs near the latch, theelement 50 relays an impact signal. Because localized elements 50 werenot present, though, the signal does not relay information regarding thelocality of the impact beyond the general area of the vehicle door 24.Consequently, the restraints control module 36 does not have informationregarding the precise location of the impact when making a subsequentdeployment decision. Furthermore, this arrangement of a plurality ofbend sensitive resistance elements 50 provides an ability to resolve thelocation and width of an impact event relative to the vehicle 10 bycomparing the extent of deformation between neighboring bend sensitiveresistance elements 50.

The conductive ink strip 52 of the bend sensitive resistance element 50is printed onto the flexible substrate 54. Preferably, the substrate 54is a flexible material such as polyamide. Polyester or other suitablematerials capable of providing the necessary flexibility may also beused. The flexible nature of the substrate 54 allows the bend sensitiveresistance element 50 to be disposed along a non-linear surface. Also,the flexible substrate 54 provides the flexibility necessary to allowthe ink strip 52 to structurally react in response to impact events,which is necessary for proper operation of the bend sensitive resistanceelement 50, and consequently the sensing system 35. The flexiblesubstrate 54 may have an adhesive backing which facilitates placement onstructural elements or in a housing.

The cracks are small, interspersed fissures in the ink strip 52 of thebend sensitive resistance element 50. The cracks are randomly spaced andoriented throughout the ink strip 52. The cracks are disposed along asingle side of the strip 52, making the bend sensitive resistanceelement 50 sensitive in only one direction. When used to monitor for theoccurrence of side impact events in a vehicle door 24, the surfacehaving the cracks is typically directed toward the passenger compartment16 of the vehicle 10. As the bend sensitive resistance element 50 isbent inward, such as when a side impact occurs, the cracks open andincrease the resistance of the element 50. This change in resistance canbe detected by the restraints control module 36, which continuallymonitors the resistive output of the element 50.

In addition to bend sensitive resistance elements 50, the sensor element38 may be any other type of sensor element 38 capable of being disposedin a manner that allows direct physical involvement in an impact andgathering and relaying information regarding the impact. That is, thesensor element 38 may be any other type of deformation sensor element.For example, the sensor element 38 may be a piezoelectric cable or afiber-optic cable. No matter the type of deformation sensor utilized,the sensor element 38 can be either a unitary item spanning the lengthof a vehicle structural element, or may be a plurality of elongatesensor elements 38 horizontally situated so as to be capable ofproviding azimuthal resolution of impact events.

Turning now to the operation of the sensing system 35 of the presentinvention. As discussed above, the sensor element 38 of the presentinvention is able to directly participate in a vehicle impact eventoccurring in the area of the vehicle 10 in which the sensor element 38is positioned. The sensor element 38 provides a variable output that isproportional to the extent of deformation induced in the sensor element38 by an intruding object driving the impact event. It will be notedthat the bend sensitive resistance element 50 of the preferredembodiment, due to its flexible nature and ability to have an adhesivebacking on the flexible substrate 54, is particularly easy to mount invarious locations of the vehicle 10 such that it will directlyparticipate in and therefore detect an impact, and subsequently relayinformation regarding the impact event.

FIGS. 6 a–6 c show an impact event involving a pole 58 and a vehicle 10containing a sensing system 35 according to the present invention. Thedoor 24 of the vehicle 10 contains a sensor element 38 in communicationwith a restraints control module 36. The sensor element 38 is positionedunderneath the outer skin 42 of the door 24. The figures illustrates thephysical consequences of the impact over time. As the impact progresses,the pole 58 first deforms the outer skin 42 of the vehicle door 24. Asshown in FIG. 6 b, the sensor element 38 is not involved at this pointdue to its position relative to the outer skin 42. However, as shown inFIG. 6 c, once the impact progresses to a point where the sensor element38 is situated, the pole 58 actually deforms the sensor element 38. Atthis point, the sensor element 38 is directly participating in theimpact event, which is necessary for the operation of deformationsensors. As the impact progresses further, the sensor element 38 deformsfurther. The sensor element 38 provides an output signal 60 that, whenaltered, indicates the occurrence of an impact event. For example, fiberoptic deformation sensors provide an output signal 60 that consists ofthe transmission of light. In the preferred embodiment, the resistanceof the bend sensitive resistance element 50 is the output signal 60, andincreases as deformation progresses due to increased opening of thecracks in the ink strip 52. The restraints control module 36 detects anychange in the output signal 60, as described below, and makes adeployment decision based thereon.

FIGS. 7 a–7 c illustrate a corresponding output signal 60 transmitted bythe sensor element 38 during the impact event depicted in FIGS. 6 a–6 c.As the impact event progresses over time, the output signal 60 variesdepending on the extent of deformation of the sensor element 38. For thepreferred embodiment, which utilizes a bend sensitive resistance element50, the output signal 60 corresponds to the resistance of the sensorelement 38. In FIG. 7 a, before the impact event has occurred, theoutput signal 60 remains constant at a threshold output level 62. As thepole 58 deforms the outer skin 42 of the door 24 but has yet to reachthe sensor element 38, the electrical output signal 60 remains constantat the threshold level 62, as illustrated in FIG. 7 b. Once the sensorelement 38 is involved in the impact event, and deformation of thesensor element 38 occurs, the output signal 60 changes to reflect theseverity of the impact.

The amplitude 64 of the change in the output signal 60 indicates theextent of the deformation. That is, as more deformation is imposed onthe sensor element 38, the output signal 60 changes more dramaticallyfrom the threshold output level 62. For the preferred embodimentutilizing bend sensitive resistance elements 50, it has been observedthat the resistance typically changes by a factor of approximately tenwhen deployment-type events are encountered. The output signal 60 of thesensor element 38 will return to its original value, i.e., the thresholdoutput level 62, when and if the sensor element 38 returns to itsoriginal and undeformed state. The slope 66 of the change in the outputsignal 60 indicates the rate at which the deformation occurred. Ifdeformation occurs rapidly, the time required to achieve the change inthe output signal 60 is relatively brief, producing a steep slope 66.Conversely, if the deformation occurs relatively slowly over time, theslope 66 will be correspondingly gradual in nature. Both the amplitude64 and the slope 66 of the change in the output signal 60 can be used bythe restraints control module 36 to make more effective deploymentdecisions. For example, if the amplitude 64 indicates a relativelysevere impact event, the restraints control module 36 can deployrestraints to a greater extent, such as involving more restraints ordeploying one restraint more fully. Also, if the slope 66 indicates arelatively slow impact event, the restraints control module 36 can slowdown the rate of deployment.

The output signal 60 is sent via the signal-processing module 48 to therestraints control module 36, which then interprets the signal 60 todiscriminate between different types and severity of impacts. Given thatdifferent types of objects involved in impact events, such as poles 58,barriers, pedestrians and other vehicles, will produce different outputsignals 60 for a given speed and acceleration of the vehicle 10 duringthe impact event, the signal 60 will vary accordingly. The ability ofthe sensing system 35 of the present invention to provide azimuthalresolution of an impact event adds another degree of variance to theoutput signal 60. The resulting ability to distinguish, for example,pole-impact events from low-speed barrier impacts, will provide a moreaccurate decision from the restraints control module 36 for when todeploy a restraint device, which restraint to deploy, and the extent ofsuch deployment. Furthermore, the ability to determine the location andwidth of impact with the vehicle 10 will allow for more effectivedecisions regarding which restraints need be deployed.

The restraints control module 36 includes hardware and/or software forprocessing incoming output signals 60, determining if a passiverestraint threshold has been met and sending a deployment signal to thepassive restraints, such as the front airbags 22, the side airbags 26,and/or the pedestrian airbag 30.

In order to further improve impact determination and passive restraintfiring decisions, one may wish to employ the output signal 60 from thesensor elements 38 of the present invention along with the output fromthe accelerometers 32, 34. The accelerometers 32, 34 are illustrated inFIG. 1 and also provide output signals processed by the restraintscontrol module 36. While accelerometers are illustrated in the preferredembodiment, they are not necessary for the operation of the sensorelements 38 of the present invention.

For example, the particular sensor element 38 near the impact locationmay be used as the primary impact detection sensor, with the centrallymounted accelerometers employed as safing sensors. In this way, thecharacteristics of the strain detected by the sensor element 38 may betempered by the amount of acceleration experienced by the vehicle as isdetected by one or both of the accelerometers 32, 34. Another example ofimpact detection in which the different sensors are employed may includeemploying the accelerometers 32, 34 as the primary sensors for impactevents, and modifying the thresholds for the deployment decision basedupon the strain detected by a particular one of the sensor elements 38.No matter if the sensor element 38 or the accelerometers 32, 34 areutilized as the primary sensors, the azimuthal resolution provided bythe sensor elements 38 can be utilized in conjunction with output fromthe accelerometers 32, 34 to resolve the localization and/or width foran impact event. This combination of impact information provides for afurther degree of tempering, and increasing the number of possibledeployment scenarios.

The foregoing disclosure is the best mode devised by the inventors forpracticing the invention. It is apparent, however, that vehicle impactsensing systems incorporating modifications and variations will beobvious to one skilled in the art of impact sensors and systems.Inasmuch as the foregoing disclosure is intended to enable one skilledin the pertinent art to practice the instant invention, it should not beconstrued to be limited thereby but should be construed to include suchaforementioned obvious variations and be limited only by the spirit andscope of the following claims:

1. A vehicle impact sensing system for detecting vehicular impactscausing structural elements of a vehicle to deform, the vehicle impactsensing system comprising: a plurality of bend sensitive resistanceelements longitudinally spaced along a an elongated structural elementof said vehicle, wherein each of the plurality of bend sensitiveresistance elements are capable of generating an independent resistanceoutput signal, the bend sensitive resistance elements each have a stripof conductive ink containing a plurality of cracks along a surfacethereof, at least one passive restraint disposed within said vehicle,and a controller in independent electrical communication with each ofthe plurality of bend sensitive resistance elements, said controllerdetects a location of an impact along the structural element bydetermining which bend sensitive elements are activated and which bendsensitive elements are not activated based on a detected change in eachof the independent resistance output signals.
 2. The vehicle impactsensing system of claim 1 wherein said structural element of saidvehicle is a structural reinforcement beam of a door of said vehicle. 3.The vehicle impact sensing system of claim 1 wherein said structuralelement of said vehicle is a bumper of said vehicle.
 4. The vehicleimpact sensing system of claim 1 wherein said at least one passiverestraint is a side airbag.
 5. The vehicle impact sensing system ofclaim 1 wherein said at least one passive restraint is a pedestrianairbag.
 6. A vehicle impact sensing system for detecting vehicularimpacts causing structural elements of a vehicle to deform, the vehicleimpact sensing system comprising: a plurality of deformation sensorelements horizontally and longitudinally spaced along a structuralelement of said vehicle, each of said plurality of sensor elements beingcapable of generating a variable output signal; at least one deployablerestraint disposed within said vehicle; and a controller in electricalcommunication with said plurality of deformation sensor elements andsaid at least one deployable restraint, said controller detects alocation of an impact along said structural element by determining whichdeformation sensor elements are activated and which deformation sensorelements are not activated based on a detected change in each of thevariable output signals.
 7. The vehicle impact sensing system of claim 6wherein said variable output signal of each of said deformation sensorelements is indicative of a resistance of each of said deformationsensor elements.
 8. The vehicle impact sensing system of claim 6 whereinsaid structural element of said vehicle is a structural reinforcementbeam of a door of said vehicle.
 9. The vehicle impact sensing system ofclaim 6 wherein said structural element of said vehicle is a bumper ofsaid vehicle.
 10. A vehicle impact sensing system for detectingvehicular impacts causing structural elements of a vehicle to deform,the vehicle impact sensing system comprising: a plurality of deformationsensor elements longitudinally spaced along an elongated structuralelement of said vehicle, each of said plurality of sensor elements beingcapable of generating a variable output signal; at least one passiverestraint disposed within said vehicle; at least one accelerometer; anda controller in independent electrical communication with each of saidplurality of deformation sensor elements, said accelerometer and said atleast one passive restraint, said controller detects a location of animpact along the structural element by determining which deformationsensor elements are activated and which deformation sensor elements arenot activated based on a detected change in each of the variable outputsignals and deploys said at least one passive restraint.
 11. The vehicleimpact sensing system of claim 10 wherein said at least oneaccelerometer is oriented to detect acceleration in a longitudinaldirection of said vehicle.
 12. The vehicle impact sensing system ofclaim 10 wherein said at least one accelerometer is oriented to detectacceleration in a lateral direction of said vehicle.
 13. The vehicleimpact sensing system of claim 10 wherein said at least one passiverestraint is a side airbag.
 14. The vehicle impact sensing system ofclaim 11 wherein said at least one passive restraint is a front airbag.15. The vehicle impact sensing system of claim 11 wherein said at leastone passive restraint is a pedestrian airbag.